Display substrate, display device and high-precision metal mask

ABSTRACT

Display substrate, display device, high-precision metal mask are provided. Display substrate includes: first, second, and third sub-pixels; in first direction, first and third sub-pixels are alternately arranged to form first sub-pixel rows, second sub-pixels form second sub-pixel rows; in second direction, first and second sub-pixel rows are alternately arranged; two first and two third sub-pixels in two adjacent rows and two adjacent columns form 2*2 array; in the array, two first sub-pixels are in different rows and in different columns, so are the two third sub-pixels, connection lines of centers of two first and two third sub-pixels form virtual quadrilateral, second sub-pixel is within virtual quadrilateral; for multiple distances from centers of two first and two third sub-pixels corresponding to same virtual quadrilateral to center of second sub-pixel, at least two distances are different. Brightness centers of virtual pixels have more uniform distribution.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. national phase of PCT Application No.PCT/CN2020/119229 filed on Sep. 30, 2020, which claims a priority of PCTApplication No. PCT/CN2020/114622 filed on Sep. 10, 2020, which areincorporated herein by reference in their entireties.

TECHNICAL FIELD

The present disclosure relates to the field of display technology, andin particular to a display substrate, a display device and ahigh-precision metal mask.

BACKGROUND

An organic light-emitting diode (OLED) display device includes a basesubstrate, a light-emitting layer, and an encapsulation protectionlayer. The light-emitting layer includes sub-pixels arranged in an arrayon the base substrate. For each sub-pixel, a fine metal mask (FMM) isgenerally used to evaporate an organic light-emitting material onto thecorresponding sub-pixel position of the array substrate. With thedevelopment of technology, people have increasingly high requirementsfor resolution of display devices.

At present, limited to production level of the FMM and precision of theevaporation process, it is difficult to increase the resolution byreducing sub-pixel sizes and reducing pixel pitches. A commonly usedmethod is sub-pixel rendering (SPR) technology, which uses sub-pixelsthat share certain positions in different pixels, so as to userelatively few sub-pixels to simulate a higher resolution. SPR increasesthe aperture ratio of the light-emitting layer, and improves theaperture ratio and lifetime of the display device. However, in the pixelarrangement structure in the conventional technologies, brightnesscenters of virtual pixels usually have a nonuniform distribution. As aresult, when displaying some characters and specific graphics,graininess and distortion of the display are inevitably caused.

SUMMARY

In view of the above, the present disclosure provides a displaysubstrate, a display device, and a high-precision metal mask, which areused to solve the problem of graininess and distortion of display causedby nonuniform arrangement of brightness centers of virtual pixels of thepixel arrangement structure in the conventional technologies.

To solve the above technical problem, the present disclosure adopts thefollowing technical solutions.

In a first aspect, embodiments of the present disclosure provide adisplay substrate, including: first sub-pixels, second sub-pixels andthird sub-pixels;

-   -   in a first direction, the first sub-pixels and the third        sub-pixels are alternately arranged to form first sub-pixel        rows, and the second sub-pixels form second sub-pixel rows;    -   in a second direction, the first sub-pixel rows and the second        sub-pixel rows are alternately arranged, and the first direction        and the second direction are substantially perpendicular;    -   two first sub-pixels and two third sub-pixels in two adjacent        rows and two adjacent columns form a 2*2 array; in the 2*2        array, the two first sub-pixels are in different rows and in        different columns, the two third sub-pixels are in different        rows and in different columns, connection lines of centers of        the two first sub-pixels and the two third sub-pixels form a        virtual quadrilateral, and the second sub-pixel is within the        virtual quadrilateral;    -   for multiple distances that are from the centers of the two        first sub-pixels and the centers of the two third sub-pixels        corresponding to a same virtual quadrilateral to a center of the        second sub-pixel, at least two distances among the multiple of        distances are different;    -   the third sub-pixel has a symmetry axis along a first oblique        line direction and a symmetry axis along a second oblique line        direction, and a width of the third sub-pixel in the first        oblique line direction is different from that in the second        oblique line direction; and/or, the first sub-pixel has a        symmetry axis along a first oblique line direction and a        symmetry axis along a second oblique line direction, and a width        of the first sub-pixel in the first oblique line direction is        different from that in the second oblique line direction;    -   the second oblique line direction is substantially perpendicular        to the first oblique line direction, and the second oblique line        direction and the first oblique line direction intersect both        the first direction and the second direction.

Optionally, an interior angle of the virtual quadrilateral is in a rangeof 700 to 120°.

Optionally, the two first sub-pixels and the two third sub-pixelscorresponding to a same virtual quadrilateral surround one secondsub-pixel, and a minimum distance among distances that are from otherfirst sub-pixels and other third sub-pixels outside the virtualquadrilateral to the surrounded second sub-pixel, is greater than, aminimum distance among distances that are from the two first sub-pixelsand two third sub-pixels corresponding to the same virtual quadrilateralto the surrounded second sub-pixel.

Optionally, for the multiple distances that are from the centers of thetwo first sub-pixels and the centers of the two third sub-pixelscorresponding to a same virtual quadrilateral to the center of thesecond sub-pixel, a ratio of any two distances among the multipledistances is in a range of 0.7 to 1.3.

Optionally, a difference between the distances from the centers of thetwo first sub-pixels to the center of the second sub-pixel correspondingto a same virtual quadrilateral, is smaller than, a difference betweenthe distances from the centers of the two third sub-pixels to the centerof the second sub-pixel corresponding to the same virtual quadrilateral.

Optionally, for the same virtual quadrilateral, the distances from thecenters of the two first sub-pixels to the center of the secondsub-pixel are substantially equal.

Optionally, each of the distances from the centers of the two firstsub-pixels and the centers of the two third sub-pixels corresponding toa same virtual quadrilateral to the center of the second sub-pixelranges from 20 μm to 60 μm.

Optionally, the first sub-pixel and the third sub-pixel have differentshapes.

Optionally, the first sub-pixel and the third sub-pixel each are anaxisymmetric pattern, and a symmetry axis of at least one firstsub-pixel and a symmetry axis of at least one third sub-pixel areparallel and do not coincide; and/or,

-   -   the first sub-pixel has a symmetry axis in a first oblique        direction, and symmetry axes in the first oblique direction of        two adjacent first sub-pixels in the first oblique direction do        not coincide; and/or,    -   the third sub-pixel has a symmetry axis in a first oblique        direction, and symmetry axes in the first oblique direction of        two adjacent third sub-pixels in the first oblique direction do        not coincide.

Optionally, in at least one virtual quadrilateral, the distances fromthe center of the second sub-pixel to the centers of the two thirdsub-pixels are not equal, and the distances from the center of thesecond sub-pixel to the centers of the two first sub-pixels areapproximately equal; or,

-   -   in at least one virtual quadrilateral, the distances from the        center of the second sub-pixel to the centers of the two third        sub-pixels are approximately equal, and the distance from the        center of the second sub-pixel to the centers of the two first        sub-pixels are approximately equal; or,    -   in at least one virtual quadrilateral, the distances from the        center of the second sub-pixel to the centers of the two third        sub-pixels are approximately equal, and the distances from the        center of the second sub-pixel to the centers of the two first        sub-pixels are not equal.

Optionally, in at least one virtual quadrilateral, the distance from thesecond sub-pixel to a first one of the third sub-pixels is L1, and thedistance from the second sub-pixel to a center of a second one of thethird sub-pixels is L2, and the distances from the second sub-pixel tothe two first sub-pixels are both L1; or,

-   -   in at least one virtual quadrilateral, each of the distances        from the second sub-pixel to the two third sub-pixels and the        distance from the second sub-pixel to the two first sub-pixels        is L1; or,    -   in at least one virtual quadrilateral, each of the distances        from the second sub-pixel to the two third sub-pixels and the        distances from the second sub-pixel to the two first sub-pixels        is L2; or,    -   in at least one virtual quadrilateral, the distances from the        second sub-pixel to the two third sub-pixels are both L1, and        the distance from the second sub-pixel to a first one of the        first sub-pixels is L1, and the distance from the second        sub-pixel to a second one of first sub-pixels is L2; or,    -   in at least one virtual quadrilateral, the distances from the        second sub-pixel to the two third sub-pixels are both L2, and        the distances from the second sub-pixel to the two first        sub-pixels are both L1;    -   L2 is greater than L1.

Optionally, a difference between L2 and L1 is greater than or equal to 1μm, and a range of L1 is 12 μm to 30 μm.

Optionally, the virtual quadrilateral is a right-angled trapezoid, twointerior angles of the virtual quadrilateral each are 90°, one of othertwo interior angles of the virtual quadrilateral is an obtuse angle, andone of the other two interior angles of the virtual quadrilateral is anacute angle.

Optionally, a range of each of all interior angles of the virtualquadrilateral is 700 to 120°.

Optionally, some of the virtual quadrilaterals each are a firstparallelogram, and some of the virtual quadrilaterals each are a secondparallelogram; in a row direction and in a column direction, the firstparallelograms and the second parallelograms are arranged alternately;at least one interior angle of the first parallelogram and at least oneinterior angle of the second parallelogram are different.

Optionally, a range of each of an acute angle of the first parallelogramand an acute angle of the second parallelogram is greater than or equalto 700 and less than 90°.

Optionally, for the third sub-pixel and/or the first sub-pixel, adifference between the width in the first oblique line direction and thewidth in the second oblique line direction is greater than or equal to 1μm.

Optionally, for the second sub-pixel, a width in the first oblique linedirection and a width in the second oblique line direction aredifferent.

Optionally, in the virtual quadrilateral, the second sub-pixel isapproximately symmetrical with respect to a connection line of thecenters of the two third sub-pixels that are adjacent in the firstoblique line direction or the second oblique line direction, and isapproximately symmetrical with respect to a connection line of thecenters of the two first sub-pixels that are adjacent in the secondoblique line direction or the first oblique line direction.

Optionally, four virtual quadrilaterals in an array form a virtualpolygon, and the first sub-pixels and the third sub-pixels are oncorners or edges of the virtual polygon, and are alternately distributedon the edges or the corners of the virtual polygon in a clockwisedirection.

Optionally, in the virtual polygon, the centers of the third sub-pixelsin a same row are approximately on a straight line parallel to a rowdirection, and/or the centers of the third sub-pixels in a same columnare approximately on a straight line parallel to a column direction.

Optionally, in the virtual polygon, the centers of the second sub-pixelsin a same row are approximately on a straight line parallel to a rowdirection, and/or the centers of the second sub-pixels in a same columnare approximately on a straight line parallel to a column direction.

Optionally, respective total opening areas of the third sub-pixels, thesecond sub-pixels, and the first sub-pixels are sequentially decreased,the total opening area of the first sub-pixels is x, the total openingarea of the second sub-pixels is a*x, and the total opening area of thethird sub-pixels is b*x, where 0.5≤a≤0.8 and 1≤b≤2.2.

Optionally, each of shapes of the first sub-pixel, the second sub-pixel,and the third sub-pixel is any of a polygon, a circle, or an ellipse.

Optionally, each of the shapes of the first sub-pixel, the secondsub-pixel, and the third sub-pixel is any of a quadrilateral, a hexagon,an octagon, a quadrilateral with rounded corners, a hexagon with roundedcorners, an octagon with rounded corners, a circle, or an ellipse.

Optionally, the first sub-pixel is a red sub-pixel, the second sub-pixelis a green sub-pixel, and the third sub-pixel is a blue sub-pixel.

In a second aspect, embodiments of the present disclosure provide adisplay device including the display substrate according to the firstaspect.

Optionally, the display device further includes a pixel defining layer,the pixel defining layer includes multiple pixel defining layeropenings, each of the first sub-pixels, the second sub-pixels and thethird sub-pixels corresponds to a pixel defining layer opening of themultiple pixel defining layer openings, and shapes of the firstsub-pixel, the second sub-pixel and the third sub-pixel areapproximately the same as shapes of their respective pixel defininglayer openings.

Optionally, the first sub-pixel includes multiple films, and themultiple films of the first sub-pixel at least partially cover a regionoutside the pixel defining layer opening; and/or, the second sub-pixelincludes multiple films, and the multiple films of the second sub-pixelat least partially cover a region outside the pixel defining layeropening; and/or, the third sub-pixel includes multiple films, and themultiple films of the third sub-pixel at least partially cover a regionoutside the pixel defining layer opening.

Optionally, at least some of the multiple pixel defining layer openingsare different in shapes or areas

Optionally, at least some of the pixel defining layer openingscorresponding to the first sub-pixels or the third sub-pixels aredifferent in shapes or areas.

Optionally, at least some of the pixel defining layer openingscorresponding to the first sub-pixels or the third sub-pixels havedifferent minimum distances from their respective adjacent openings.

In a third aspect, embodiments of the present disclosure provide ahigh-precision metal mask for manufacturing the display substrateaccording to the first aspect, the first sub-pixel includes multiplefilms, and the second sub-pixel includes multiple films, the thirdsub-pixel includes multiple films, the mask includes multiple openingregions, and the multiple opening regions include: a first openingregion corresponding to a shape and a distribution of at least one filmin the first sub-pixel, or a second opening region corresponding to ashape and a distribution of at least one film in the second sub-pixel,or a third opening region corresponding to a shape and a distribution ofat least one film in the third sub-pixel.

The beneficial effects of the above technical solutions of the presentdisclosure are as follows.

In the embodiments of the present disclosure, on the one hand, bysharing sub-pixels, higher resolution can be achieved; on the otherhand, the widths of the first pixel and/or the third sub-pixel indifferent oblique line directions are arranged to be different, in thisway, for multiple distances from the centers of the two first sub-pixelsand the centers of the two third sub-pixels in the virtual quadrilateralto a center of the second sub-pixel, at least two distances among themultiple distances are different, so that brightness centers of virtualpixels are arranged more uniformly, avoiding graininess and distortionof the display and improving display effect. In addition, without theneed of moving positions of the sub-pixels, the brightness centers ofthe virtual pixels are moved, which has a low implementation cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a pixel arrangement structure in therelated technologies;

FIG. 2 is a schematic diagram of a display substrate according toembodiments of the present disclosure;

FIGS. 3 and 5 are schematic diagrams of a display substrate according toa first embodiment of the present disclosure;

FIGS. 4 and 6 are schematic diagrams of a display substrate according toa second embodiment of the present disclosure;

FIG. 7-13 are schematic diagrams of a positional relationship between adisplay substrate and opening regions of a light-emitting layeraccording to embodiments of the present disclosure;

FIG. 14-15 are schematic diagrams of a display substrate according to athird embodiment of the present disclosure;

FIG. 16-18 are schematic diagrams of a high-precision metal mask used tomanufacture first sub-pixels, second sub-pixels, and third sub-pixels ina display substrate according to above embodiments; and

FIG. 19 is a schematic diagram of a cross-sectional structure of adisplay substrate according to embodiments of the present disclosure.

DETAILED DESCRIPTION

To make objectives, technical solutions, and advantages of embodimentsof the present disclosure clearer, the technical solutions of theembodiments of the present disclosure will be clearly and completelydescribed hereinafter with reference to the accompanying drawings of theembodiments of the present disclosure. The described embodiments are apart rather than all of the embodiments of the present disclosure. Basedon the described embodiments of the present disclosure, all otherembodiments obtained by those skilled in the art fall within theprotection scope of the present disclosure.

Reference is made to FIG. 1 . FIG. 1 is a schematic diagram of a pixelarrangement structure in the related technologies. In FIG. 1 , bluesub-pixels (B) and red sub-pixels (R) are square. In this structure, inthe (i−1)-th row, a distance 11 between brightness centers of virtualpixel in the j-th column and the virtual pixel in the (j+1)-th column(the black dots in the figure) is greater than a distance 12 betweenbrightness centers of the virtual pixel in the j-th column and thevirtual pixel in the (j−1)-th column; in the i-th row, a distancebetween brightness centers of the virtual pixel in the j-th column andthe virtual pixel in the (j+1)-th column (the black dots in the figure)is smaller than a distance between brightness centers of the virtualpixel in the j-th column and the virtual pixel in the (j−1)-th column;which results in a perceptible sense of distortion and graininess tohuman eyes when displaying vertical lines or an image dominated byvertical lines.

In order to solve the above problem, reference is made to FIG. 2 .Embodiments of the present disclosure provide a display substrate,including: first sub-pixels R, second sub-pixels G, and third sub-pixelsB.

In a first direction, the first sub-pixels R and the third sub-pixels Bare alternately arranged to form first sub-pixel rows, and the secondsub-pixels G form second sub-pixel rows.

In a second direction, the first sub-pixel rows and the second sub-pixelrows are alternately arranged, and the first direction and the seconddirection are perpendicular or substantially perpendicular.

Two first sub-pixels R and two third sub-pixels B distributed in twoadjacent rows and two adjacent columns form a 2*2 array. In the 2*2array, the two first sub-pixels R are located in different rows and indifferent columns, the two third sub-pixels B are located in differentrows and in different columns, connection lines of centers of the twofirst sub-pixels R and the two third sub-pixels B form a virtualquadrilateral, and the sub-pixel G is located within the virtualquadrilateral.

For multiple distances from the centers of the two first sub-pixels Rand the centers of the two third sub-pixels B corresponding to the samevirtual quadrilateral to the center of the second sub-pixel G, at leasttwo distances among the multiple distances are different.

The third sub-pixel B has a symmetry axis along a first oblique linedirection and a symmetry axis along a second oblique line direction. Thewidth of the third sub-pixel B in the first oblique line direction isdifferent from that in the second oblique line direction (one of thewidths is W1 and the other of the widths is H1), the second oblique linedirection is perpendicular or substantially perpendicular to the firstoblique line direction, and the second oblique line direction and thefirst oblique line direction intersect both the first direction and thesecond direction.

It can be seen from FIG. 2 that, the first sub-pixel R and thirdsub-pixel B which are adjacent and are in a same row, and a secondsub-pixel G in the next row, form a virtual pixel (the triangle in thefigure). Moreover, adjacent virtual pixels in a same row share a firstsub-pixel R or a third sub-pixel B.

In addition, it can also be seen from FIG. 2 that, in the embodiments ofthe present disclosure, a difference of distances each of which isbetween brightness centers of adjacent virtual pixels in a same row issmaller than a difference of distances each of which is betweenbrightness centers of adjacent virtual pixels in a same row in therelated technologies. That is, the arrangement of the brightness centersof the virtual pixels in the embodiments of the present disclosure ismore uniform.

In the embodiments of the present disclosure, on the one hand, bysharing sub-pixels, higher resolution can be achieved; on the otherhand, the widths of the third sub-pixel in different oblique linedirections are arranged to be different, in this way, for multipledistances from the centers of the two first sub-pixels and the centersof the two third sub-pixels in the virtual quadrilateral to a center ofthe second sub-pixel, at least two distances among the multipledistances are different, so that the brightness centers of the virtualpixels are more uniform, avoiding graininess and distortion of thedisplay and improving display effect. In addition, without the need ofshifting positions of the sub-pixels, the brightness centers of thevirtual pixels are shifted, which has a low implementation cost.

In the embodiments of the present disclosure, optionally, for themultiple distances from the centers of the two first sub-pixels and thecenters of the two third sub-pixels in the same virtual quadrilateral tothe center of the second sub-pixel, at least two distances among themultiple distances are the same.

In the embodiments of the present disclosure, optionally, a range of aninterior angle of the virtual quadrilateral is 70°-120°.

In the embodiments of the present disclosure, optionally, two firstsub-pixels and two third sub-pixels corresponding to a same virtualquadrilateral surround a second sub-pixel; a minimum distance amongdistances that are from other first sub-pixels and other thirdsub-pixels outside this virtual quadrilateral, is greater than, aminimum distance among distances that are from the two first sub-pixelsand the two third sub-pixels corresponding to this virtual quadrilateralto the surrounded second sub-pixel. The distance may be a distancebetween boundaries of sub-pixels. In addition, if patterns of thesub-pixels have rounded corners, the distance between the roundedcorners may be partially deviated. Therefore, the error caused by therounded corners, or the measurement error, needs to be considered forthe distance, for example, for a deviation of about 3 microns, it isregarded as equivalent.

In the embodiments of the present disclosure, optionally, for themultiple distances that are from the centers of the two first sub-pixelsand the centers of the two third sub-pixels corresponding to a samevirtual quadrilateral to the center of the second sub-pixel, a ratio ofany two distances among the multiple distances is in a range of 0.7 to1.3

In the embodiments of the present disclosure, optionally, a differencebetween the distances from the centers of the two first sub-pixels tothe center of the second sub-pixel corresponding to a same virtualquadrilateral, is smaller than, a difference between the distances fromthe centers of the two third sub-pixels to the center of the secondsub-pixel corresponding to the same virtual quadrilateral.

Further optionally, for same virtual quadrilateral, the distances fromthe centers of the two first sub-pixels to the center of the secondsub-pixel are equal or substantially equal.

In the embodiments of the present disclosure, optionally, a differencebetween the distances from the centers of the two first sub-pixels tothe center of the second sub-pixel corresponding to a same virtualquadrilateral, is smaller than, a difference between the distances fromthe centers of the two third sub-pixels to the center of the secondsub-pixel corresponding to the same virtual quadrilateral.

Optionally, each of the distances from the centers of the two firstsub-pixels and the centers of the two third sub-pixels corresponding toa same virtual quadrilateral to the center of the second sub-pixelranges from 20 μm to 60 μm. Further, optionally, each of the distancesfrom the centers of the two first sub-pixels and the centers of the twothird sub-pixels corresponding to a same virtual quadrilateral to thecenter of the second sub-pixel ranges from 25 to 50 μm, or, 30 to 48 μm.

In the embodiments of the present disclosure, optionally, the firstsub-pixel and the third sub-pixel have different shapes. For example,one of them is a square and the other is an oblong; or, the firstsub-pixel and the third sub-pixel are both oblongs, but theirlength-width ratios are different.

In the embodiments of the present disclosure, optionally, when the firstsub-pixel and/or the third sub-pixel are oblong, the length-width ratiomay be 1.2 to 1.8.

In the embodiments of the present disclosure, optionally, a length-widthratio of the second sub-pixel may be 1.2 to 1.3.

In the embodiments of the present disclosure, optionally, the firstsub-pixel and the third sub-pixel each are an axisymmetric pattern, anda symmetry axis of at least one first sub-pixel and a symmetry axis ofat least one third sub-pixel are parallel and do not coincide; and/or,

the first sub-pixel has a symmetry axis in a first oblique direction,and symmetry axes in the first oblique direction of two adjacent firstsub-pixels in the first oblique direction do not coincide; and/or,

the third sub-pixel has a symmetry axis in a the oblique direction, andsymmetry axes in the first oblique direction of two adjacent thirdsub-pixels in the first oblique direction do not coincide.

As mentioned in the above embodiments, in the virtual quadrilateral, formultiple distances from the centers of the two first sub-pixels R andthe centers of the two third sub-pixels B to the center of the secondsub-pixel G, at least two distances among the multiple distances aredifferent. Descriptions are provided in the following with examples.

In some embodiments of the present disclosure, optionally, reference ismade to FIG. 3 . In a first embodiment of the present disclosure, in atleast one of the virtual quadrilaterals (see the two virtualquadrilaterals on the left side of FIG. 3 ), the distance D1 between thecenter of the second sub-pixel G and the center of the first one of thethird sub-pixels B is different from the distance D2 between the centerof the second sub-pixel G and the center of the second one of the thirdsub-pixels B; the distance between the center of the second sub-pixel Gand the center of the first one of the first sub-pixels R isapproximately equal to the distance between the center of the secondsub-pixel G and the center of the second one of the first sub-pixels R,which both are D3. Optionally, D2 is greater than D1. Optionally, D1 isgreater than D3.

In some embodiments of the present disclosure, optionally, reference ismade to FIGS. 3 and 4 . In at least one of the virtual quadrilaterals(see the two virtual quadrilaterals on the right side of FIG. 3 and thevirtual quadrilaterals in FIG. 4 ), the distance from the center of thesecond sub-pixel to the centers of the two third sub-pixels areapproximately equal, which both are D1 or D2; and the distances from thecenter of the second sub-pixel to the centers of the two firstsub-pixels are approximately equal, which both are D3. Optionally, D2 isgreater than D1. Optionally, D1 is greater than D3.

In the first embodiment shown in FIG. 3 , the third sub-pixels B locatedin the same row have the same width in the first oblique line direction(that is, directions of their long sides are the same), the thirdsub-pixels B located in the same column have the same width in the firstoblique line direction (that is, directions of their long sides are thesame), and the third sub-pixels B located in adjacent rows and adjacentcolumns have different widths in the first oblique direction (that is,directions of their long sides are perpendicular or substantiallyperpendicular to each other, and the direction of the long side in FIG.3 is indicated by a dashed arrow).

In a second embodiment shown in FIG. 4 , all the third sub-pixels B havethe same width in the first oblique line direction (that is, directionsof their long sides are the same, and the direction of the long side inFIG. 4 is indicated by a dotted arrow).

In the embodiments shown in FIGS. 3 and 4 , the first sub-pixels R andthe third sub-pixels B located in the same row are not on a samestraight line, and the first sub-pixels R and the third sub-pixels Blocated in the same column are not on a same straight line.

In the embodiments of the present disclosure, four virtualquadrilaterals arranged in an array form a virtual polygon (it may be avirtual quadrilateral or a virtual octagon, etc.), and the firstsub-pixels and the third sub-pixels are located on corners or edges ofthe virtual polygon, and are alternately distributed on the edges or thecorners of the virtual polygon in a clockwise direction.

In the embodiments of the present disclosure, in the virtual polygon,the centers of the third sub-pixels located in a same row areapproximately on a straight line parallel to a row direction, and/or thecenters of the third sub-pixels located in a same column areapproximately on a straight line parallel to a column direction.

In the embodiments of the present disclosure, in the virtual polygon,the centers of the second sub-pixels located in a same row areapproximately on a straight line parallel to a row direction, and/or thecenters of the second sub-pixels located in a same column areapproximately on a straight line parallel to a column direction.

In the embodiments shown in FIGS. 3 and 4 , four virtual quadrilateralsarranged in an array form a virtual octagon, and the virtual octagonserves as a repeating unit. The centers of four first sub-pixels R andfour third sub-pixels B are located at vertices of the virtual octagon,and the first sub-pixels R and the third sub-pixels B are alternatelyarranged clockwise. One of the third sub-pixels B is located in thecenter of the virtual octagon.

In the embodiments of the present disclosure, optionally, for thevirtual quadrilateral, the second sub-pixel G is approximatelysymmetrical with respect to a connection line of the centers of thethird sub-pixels B that are adjacently arranged in the first obliqueline direction or the second oblique line direction. That is, the secondsub-pixel G is on a symmetry axis of two third sub-pixels B. Optionally,as shown in FIG. 5 , for one of the third sub-pixels B, a width in adirection of the symmetry axis is smaller than a width in a direction ofthe other symmetry axis; for the other of the third sub-pixels B, awidth in the direction of the symmetry axis is greater than a width inthe direction of the other symmetry axis (that is, the long sides of thetwo third sub-pixels B of the virtual quadrilateral are perpendicular orapproximately perpendicular). Or, as shown in FIG. 6 , for each of thetwo third sub-pixels B, a width in a direction of the symmetry axis issmaller than a width in a direction of the other symmetry axis (that is,the long sides of the two third sub-pixels B of the virtualquadrilateral are parallel).

For different circumstances in the above embodiments, distances betweenthe sub-pixels of the virtual quadrilateral are changed; there exist atleast some virtual quadrilaterals in which distances from the two thirdsub-pixels B to the second sub-pixel G are different. Description areprovided in the following with examples.

A distance between sub-pixels refers to a vertical distance between twoadjacent parallel edges of the sub-pixels.

In some embodiments of the present disclosure, optionally, reference ismade to FIG. 5 . In at least one of the virtual quadrilaterals (the twovirtual quadrilaterals on the left of FIG. 5 ), the distance between thesecond sub-pixel G and the first one of the third sub-pixels B is L1,the distance between the second sub-pixel G and the second one of thethird sub-pixels B is L2, and the distances from the second sub-pixel Gto the two first sub-pixels R are both L1, where L2 is greater than L1.

In some embodiments of the present disclosure, optionally, reference ismade to FIG. 5 and FIG. 6 . In at least one of the virtualquadrilaterals, each of the distances from the second sub-pixel G to thetwo third sub-pixels B and the two first sub-pixels R is L1 (the twovirtual quadrilaterals on the right side of FIG. 5 , and the threevirtual quadrilaterals except for the one on the upper left corner ofFIG. 6 ) or L2 (not shown), where L2 is greater than L1.

In some embodiments of the present disclosure, optionally, reference ismade to FIG. 6 (the virtual quadrilateral in the upper left corner ofFIG. 6 ). In at least one of the virtual quadrilaterals, the distancefrom the second sub-pixel G to the two third sub-pixels B are both L2,and the distances from the second sub-pixel G to the two firstsub-pixels R are both L1, where L2 is greater than L1.

In the above embodiments, optionally, a difference between L2 and L1 isgreater than or equal to 1 μm, and further optionally, the differencebetween L2 and L1 is greater than or equal to 2 μm or 3 μm.

In the above embodiments, optionally, a range of L1 is 12-30 m, furtheroptionally, the range of L1 is 14-28 μm, and further optionally, therange of L1 is 16-26 μm.

In the embodiments of the present disclosure, optionally, a range ofeach of all interior angles of the virtual quadrilateral is 700 to 120°.Further optionally, the interior angles of the virtual quadrilateralinclude at least one obtuse angle or at least one acute angle.

In the embodiments of the present disclosure, optionally, reference ismade to FIGS. 3 and 5 . The virtual quadrilateral is a right-angledtrapezoid, two interior angles thereof each are 90°, and one of theother two interior angles thereof is an obtuse angle which is X°, andone of the other two interior angles thereof is an acute angle which isY°. The range of obtuse angle is greater than 900 and less than or equalto 100°, further optionally, being 91°-96°. The range of acute angle isgreater than or equal to 80° and less than 90°, and further optionally,being 84°-89°.

It can be seen from FIGS. 3 and 5 that, after a virtual quadrilateral isrotated 90°+X° or rotated 90°+Y° around the center of the thirdsub-pixel located in the center of the virtual octagon, it may coincidewith a diagonal virtual quadrilateral.

In the embodiments of the present disclosure, optionally, some of thevirtual quadrilaterals each are a first parallelogram, and some of thevirtual quadrilaterals each are a second parallelogram. In a rowdirection and a column direction, the first parallelograms and thesecond parallelograms are arranged alternately; and interior angles ofthe first parallelogram and interior angles the second parallelogram aredifferent. At least one interior angle of the first parallelogram and atleast one interior angle of the second parallelogram are different; fourinterior angles of the first parallelogram may be different from fourinterior angles of the second parallelogram, or, an interior angle ofthe four interior angles of the first parallelogram and an interiorangle of the four interior angles of the second parallelogram may havethe same value in degrees but have different orientations. Theorientations being different means that, at least one of two edgesforming a first interior angle and at least one of two edges forming asecond interior angle are not parallel.

Optionally, the second parallelogram may be a rectangle. The rectangleinclude an oblong or a square.

In the embodiments of the present disclosure, optionally, reference ismade FIGS. 4 and 6 , where some of the virtual quadrilaterals areparallelograms, and some of the virtual quadrilaterals are squares. Inthe row direction and the column direction, the parallelograms and thesquares are arranged alternately.

In the embodiments of the present disclosure, optionally, a range ofeach of an acute angle Z of the first parallelogram and an acute angleof the second parallelogram is greater than or equal to 700 and lessthan 90°, and further optionally, being 84°-89°.

As can be seen from FIGS. 4 and 6 , in a virtual octagon, two diagonalvirtual quadrilaterals are parallelograms, other two diagonal virtualquadrilaterals are squares, the two squares are the same, and the twoparallelograms are different.

In the above embodiments, optionally, for the third sub-pixel, adifference between its width in the first oblique line direction and itswidth in the second oblique line direction is greater than or equal to 1μm, and further optionally, being greater than or equal to 3 μm.

In the above embodiments, optionally, the first sub-pixel R has a squareshape.

In the embodiments of the present disclosure, optionally, a certainwidth of the third sub-pixel B in the first oblique line direction orthe second oblique line direction is removed from the third sub-pixel B(the blank region on a side of the third sub-pixel B in the figure isthe removed region), to change the shape of the third sub-pixel B, so asto realize that: for multiple distances from the centers of the twofirst sub-pixels R and the centers of the two third sub-pixels B in thevirtual quadrilateral to the second sub-pixel G, at least twodifferences among the multiple distances are different.

Please refer to FIGS. 7 and 8 , frames around the first sub-pixel R, thesecond sub-pixel G, and the third sub-pixel B are opening regions of thelight-emitting layer. After a certain width of part in the first obliqueline direction or the second oblique line direction is removed from thethird sub-pixel B, a distance between an edge where the certain width ofpart is removed and the boundary of the opening region of the peripherallight-emitting layer is m1, which is greater than a distance m2 betweeneach of other edges and the boundary of the opening region of theperipheral light-emitting layer.

The above embodiments are only examples. In a virtual octagon, for eachthird sub-pixel B, the edge where the certain width of part is removedis not limited thereto, various combinations may be made, and referenceis made to FIGS. 9-13 . Referring to FIGS. 7-13 , for a third sub-pixelB, a certain width of part may be removed at any of: the two edgesperpendicular to the first oblique line direction and the two edgesparallel to the first oblique line direction.

Referring to FIG. 14 , a third embodiment of the present disclosureprovides a display substrate, including: first sub-pixels R, secondsub-pixels G, and third sub-pixels B.

In a first direction, the first sub-pixels R and the third sub-pixels Bare alternately arranged to form first sub-pixel rows, and the secondsub-pixels G form second sub-pixel rows.

In a second direction, the first sub-pixel rows and the second sub-pixelrows are alternately arranged, and the first direction and the seconddirection are perpendicular or substantially perpendicular.

Two first sub-pixels R and two third sub-pixels B distributed in twoadjacent rows and two adjacent columns form a 2*2 array. In the 2*2array, the two first sub-pixels R are located in different rows and indifferent columns, the two third sub-pixels B are located in differentrows and in different columns, connection lines of centers of the twofirst sub-pixels R and the two third sub-pixels B form a virtualquadrilateral, and the sub-pixel G is located within the virtualquadrilateral.

For multiple distances from the centers of the two first sub-pixels Rand the centers of the two third sub-pixels B corresponding to the samevirtual quadrilateral to the center of the second sub-pixel G, at leasttwo distances among the multiple distances are different.

The first sub-pixel R has a symmetry axis along a first oblique linedirection and a symmetry axis along a second oblique line direction. Thewidth of the first sub-pixel R in the first oblique line direction isdifferent from that in the second oblique line direction (one of thewidths is W2 and the other of the widths is H2), the second oblique linedirection is perpendicular or substantially perpendicular to the firstoblique line direction, and the second oblique line direction and thefirst oblique line direction intersect both the first direction and thesecond direction.

It can be seen from FIG. 14 that, the first sub-pixel R and thirdsub-pixel B which are adjacent and are in a same row, and a secondsub-pixel G in the next row, form a virtual pixel (the triangle in thefigure). Moreover, adjacent virtual pixels in a same row share a firstsub-pixel R or a third sub-pixel B.

In the embodiments of the present disclosure, on the one hand, bysharing sub-pixels, higher resolution can be achieved; on the otherhand, the widths of the first sub-pixel in different oblique linedirections are arranged to be different, in this way, for multipledistances from the centers of the two first sub-pixels and the centersof the two third sub-pixels in the virtual quadrilateral to a center ofthe second sub-pixel, at least two distances among the multipledistances are different, so that the brightness centers of the virtualpixels are more uniform, avoiding graininess and distortion of thedisplay and improving display effect. In addition, without the need ofchanging positions of the sub-pixels, the brightness centers of thevirtual pixels are changed, which has a low implementation cost.

As mentioned in the above embodiments, in the virtual quadrilateral, formultiple distances from the centers of the two first sub-pixels R andthe centers of the two third sub-pixels B to the center of the secondsub-pixel G, at least two distances among the multiple distances aredifferent. Descriptions are provided in the following with examples.

In some embodiments of the present disclosure, optionally, reference ismade to FIG. 7 (two virtual quadrilaterals on the right side of FIG. 7). In at least one of the virtual quadrilaterals, the distance betweenthe center of the second sub-pixel G and the center of the first one ofthe third sub-pixels B is approximately equal to the distance betweenthe center of the second sub-pixel G and the center of the second one ofthe thirds sub-pixel B, which both are D1; and the distance D3 betweenthe center of the second sub-pixel G and the center of the first one ofthe first sub-pixels R is different from the distance D4 between thecenter of the second sub-pixel G and the center of the second one of thefirst sub-pixels R.

In some embodiments of the present disclosure, optionally, reference ismade to FIG. 14 . In at least one of the virtual quadrilaterals (the twovirtual quadrilaterals on the left side of FIG. 14 ), the distancebetween the center of the second sub-pixel G and the center of the firstone of the third sub-pixels B is approximately equal to the distancebetween the center of the second sub-pixel G and the center of thesecond one of the third sub-pixels B, which both are D1; and thedistance between the center of the second sub-pixel G and the center ofthe first one of the first sub-pixels R is approximately the same as thedistance between the center of the second sub-pixel G and the center ofthe second one of the first sub-pixels R, which both are D3.

In the third embodiment shown in FIG. 14 , the first sub-pixels Rlocated in the same row have the same width in the first oblique linedirection (that is, directions of their long sides are the same), thefirst sub-pixels R located in the same column have the same width in thefirst oblique line direction (that is, directions of their long sidesare the same), and the first sub-pixels R located in adjacent rows andadjacent columns have different widths in the first oblique direction(that is, directions of their long sides are perpendicular orsubstantially perpendicular to each other, and the direction of the longside in FIG. 14 is indicated by a dashed arrow).

In some other embodiments of the present disclosure, optionally, for allthe first sub-pixels R, their widths in the first oblique line directionare the same (that is, the directions of their long sides are the same).

In the embodiments shown in FIG. 14 above, the first sub-pixels R andthe third sub-pixels B located in the same row are not on the samestraight line, and the first sub-pixels R and the third sub-pixels Blocated in the same column are not on a same straight line.

In the embodiments of the present disclosure, four virtualquadrilaterals arranged in an array form a virtual polygon (it may be avirtual quadrilateral or a virtual octagon, etc.), and the firstsub-pixels and the third sub-pixels are located on corners or edges ofthe virtual polygon, and are alternately distributed on the edges or thecorners of the virtual polygon in a clockwise direction.

In the embodiments of the present disclosure, in the virtual polygon,the centers of the third sub-pixels located in a same row areapproximately on a straight line parallel to a row direction, and/or thecenters of the third sub-pixels located in a same column areapproximately on a straight line parallel to a column direction.

In the embodiments of the present disclosure, in the virtual polygon,the centers of the second sub-pixels located in a same row areapproximately on a straight line parallel to a row direction, and/or thecenters of the second sub-pixels located in a same column areapproximately on a straight line parallel to a column direction.

In the embodiments shown in FIG. 14 , four virtual quadrilateralsarranged in an array form a virtual octagon, and the virtual octagonserves as a repeating unit. The centers of four first sub-pixels R andfour third sub-pixels B are located at vertices of the virtual octagon,and the first sub-pixels R and the third sub-pixels B are alternatelyarranged clockwise. One of the third sub-pixels B is located in thecenter of the virtual octagon.

In the embodiments of the present disclosure, optionally, for thevirtual quadrilateral, the second sub-pixel G is approximatelysymmetrical with respect to a connection line of the centers of thefirst sub-pixel R that are adjacently arranged in the second obliqueline direction or the first oblique line direction. That is, the secondsub-pixel G is on a symmetry axis of two first sub-pixel R. Optionally,as shown in FIG. 14 , for one of the first sub-pixel R, a width in adirection of the symmetry axis is smaller than a width in a direction ofthe other symmetry axis; for the other of the first sub-pixel R, a widthin the direction of the symmetry axis is greater than a width in thedirection of the other symmetry axis (that is, the long sides of the twofirst sub-pixels R of the virtual quadrilateral are perpendicular orapproximately perpendicular). Or, for each of the two first sub-pixelsR, a width in a direction of the symmetry axis is smaller than a widthin a direction of the other symmetry axis (that is, the long sides ofthe two first sub-pixels R of the virtual quadrilateral are parallel).

For different circumstances in the above embodiments, distances betweenthe sub-pixels of the virtual quadrilateral are changed; there exist atleast some virtual quadrilaterals in which distances from the two firstsub-pixels R to the second sub-pixel G are different. Description areprovided in the following with examples.

In some embodiments of the present disclosure, optionally, reference ismade to FIG. 15 . In at least one of the virtual quadrilaterals, each ofthe distance from the second sub-pixel G to the two third sub-pixels Band the two first sub-pixels R is L1 (two virtual quadrilaterals on theleft side of FIG. 15 ) or L2 (not shown in the figure), where L2 isgreater than L1.

In some embodiments of the present disclosure, optionally, referring toFIG. 15 , in at least one of the virtual quadrilaterals (two virtualquadrilaterals on the right side of FIG. 8 ), the distance from thesecond sub-pixel G to the two third sub-pixels B are both L1, thedistance from the second sub-pixel G to the first one of the firstsub-pixels R is L1, and the distance from the second sub-pixel G to thesecond one of the first sub-pixels R is L2, where L2 is greater than L1.

In the above embodiments, optionally, a difference between L2 and L1 isgreater than or equal to 1 μm, and further optionally, the differencebetween L2 and L1 is greater than or equal to 2 μm or 3 μm.

In the above embodiments, optionally, a range of L1 is 12-30 μm, furtheroptionally, the range of L1 is 14-28 μm, and further optionally, therange of L1 is 16-26 μm.

In the embodiments of the present disclosure, optionally, reference ismade to FIG. 14 . The virtual quadrilateral is a right-angled trapezoid,two interior angles thereof each are 90°, and one of the other twointerior angles thereof is an obtuse angle which is X°, and one of theother two interior angles thereof is an acute angle which is Y°. Therange of obtuse angle is greater than 900 and less than or equal to100°, further optionally, being 91°-96°. The range of acute angle isgreater than or equal to 80° and less than 90°, and further optionally,being 84°-89°.

It can be seen from FIG. 14 that, after a virtual quadrilateral isrotated 90°+X° or rotated 90°+Y° around the center of the thirdsub-pixel located in the center of the virtual octagon, it may coincidewith a diagonal virtual quadrilateral.

In the above embodiments, optionally, for the first sub-pixel, adifference between its width in the first oblique line direction and itswidth in the second oblique line direction is greater than or equal to 1μm, and further optionally, being greater than or equal to 3 μm.

In the embodiments shown in FIG. 14 and FIG. 15 , optionally, the thirdsub-pixel B has a square shape.

In the embodiments shown in FIGS. 3 to 6 , the third sub-pixel hasdifferent widths in different oblique line directions. In theembodiments shown in FIGS. 14 and 15 , the first sub-pixel has differentwidths in different oblique line directions. In some other embodimentsof the present disclosure, it is also feasible that: the third sub-pixelhas different widths in different oblique line directions while thefirst sub-pixel has different widths in different oblique linedirections.

In the above embodiments of the present disclosure, optionally, thesecond sub-pixel G has different widths in the first oblique linedirection and the second oblique line direction.

In the above embodiments of the present disclosure, optionally, for avirtual quadrilateral, the second sub-pixel G is approximatelysymmetrical with respect to a connection line of the centers of the twothird sub-pixels B that are adjacent in the first oblique line directionor the second oblique line direction, and is approximately symmetricalwith respect to a connection line of the centers of the two firstsub-pixels R that are adjacent in the second oblique line direction orthe first oblique line direction.

The human eyes have different resolution capabilities for the firstsub-pixel R, the second sub-pixel G, and the third sub-pixel B. Thebrightness effects of the three kinds of sub-pixels are also different.The second sub-pixel G has the largest brightness effect, followed bythe first sub-pixel R, and the third sub-pixel B has the smallestbrightness effect. In addition, organic light-emitting materials ofdifferent colors have different device life. Therefore, optionally, thetotal opening areas of the sub-pixels are as follows: the total openingarea of third sub-pixels B>the total opening area of second sub-pixelsG>the total opening area of the first sub-pixels R. That is, the totalopening area of the third sub-pixels B, the total opening area of thesecond sub-pixels G, and the total opening area of the first sub-pixelsR decrease sequentially, the total opening area of the first sub-pixelsR is x, the total opening area of the second sub-pixels G is a*x, andthe total opening area of the third sub-pixels B is b*x, where 0.5≤a≤0.8and 1≤b≤2.2. In the embodiments of the present disclosure, a totalopening area of sub-pixels refers to a total light-emitting area of thesub-pixels on the entire panel. In the above embodiments of the presentdisclosure, a case where the shapes of the first sub-pixel, the secondsub-pixel, and the third sub-pixel are all quadrilaterals with roundedcorners is taken as an example. In some embodiments, optionally, theshapes of the first sub-pixel, the second sub-pixel, and the thirdsub-pixel may be other polygons; or, the shapes of the first sub-pixel,the second sub-pixel, and the third sub-pixel may be any of: other typesof polygons with rounded corners, circle, or ellipse.

In some other embodiments of the present disclosure, optionally, each ofthe shapes of the first sub-pixel, the second sub-pixel, and the thirdsub-pixel may be selected from a quadrilateral, a hexagon, an octagon, ahexagon with rounded corners, an octagonal with rounded corners, acircle, or an ellipse.

In the above embodiments of the present disclosure, a case where thefirst sub-pixel is a red sub-pixel (R), the second sub-pixel is a greensub-pixel (G), and the third sub-pixel is a blue sub-pixel (B) is takenas an example, and the present disclosure does not exclude the use ofsub-pixels of other colors.

In the above embodiments of the present disclosure, the ratio of thenumbers of the first sub-pixels, the second sub-pixels, and the thirdsub-pixels is 1:2:1, so as to realize the sharing of sub-pixels andimprove the resolution.

Embodiments of the present disclosure also provide a display device,including the above display substrate.

In embodiments of the present disclosure, optionally, the display devicefurther includes a pixel defining layer, the pixel defining layerincludes multiple pixel defining layer openings, each of the firstsub-pixels, the second sub-pixels and the third sub-pixels correspondsto a pixel defining layer opening of the multiple pixel defining layeropenings, and shapes of the first sub-pixel, the second sub-pixel andthe third sub-pixel are approximately the same as shapes of theirrespective pixel defining layer openings.

In the embodiments of the present disclosure, optionally, the firstsub-pixel includes multiple films, and the multiple films of the firstsub-pixel at least partially cover a region outside the pixel defininglayer opening; and/or, the second sub-pixel includes multiple films, andthe multiple films of the second sub-pixel at least partially cover aregion outside the pixel defining layer opening; and/or, the thirdsub-pixel includes multiple films, and the multiple films of the thirdsub-pixel at least partially cover a region outside the pixel defininglayer opening.

In the embodiments of the present disclosure, optionally, at least someof the multiple pixel defining layer openings are different in shapes orareas.

In the embodiments of the present disclosure, optionally, at least someof the pixel defining layer openings corresponding to the firstsub-pixels or the third sub-pixels are different in shapes or areas.

In the embodiments of the present disclosure, optionally, at least someof the pixel defining layer openings corresponding to the firstsub-pixels or the third sub-pixels have different minimum distances fromtheir respective adjacent openings.

Embodiments of the present disclosure also provide a high-precisionmetal mask, which is used to manufacture the display substrate in any ofthe above embodiments. The first sub-pixel includes multiple films, thesecond sub-pixel includes multiple films, the third sub-pixel includesmultiple films, the mask includes multiple opening regions, and themultiple opening regions includes: a first opening region correspondingto a shape and a distribution of at least one film in the firstsub-pixel, or a second opening region corresponding to a shape and adistribution of at least one film in the second sub-pixel, or a thirdopening region corresponding to a shape and a distribution of at leastone film in the third sub-pixel.

A shape refers to pattern type and/or size, etc., and a distributionrefers to spacing, orientation, and/or density, etc.

Please refer to FIGS. 16-18 , which are schematic diagrams of thehigh-precision metal mask used to manufacture the first sub-pixels, thesecond sub-pixels, and the third sub-pixels of the display substrate inthe above embodiments. The first sub-pixels, the second sub-pixels orthe third sub-pixels are shown in the opening regions, and the firstsub-pixels, the second sub-pixels or the third sub-pixels are not partof the mask.

In some embodiments, a first sub-pixel includes a first effectivelight-emitting region, a second sub-pixel includes a second effectivelight-emitting region, a third sub-pixel includes a third effectivelight-emitting region, and an area of the second effectivelight-emitting region<an area of the first effective light-emittingregion<an area of the third effective light-emitting region. In adisplay substrate, the total area of all the third effectivelight-emitting regions included in the third sub-pixels>the total areaof all the second effective light-emitting regions included in thesecond sub-pixels>the total area of all the first effectivelight-emitting regions included in the first sub-pixels. In someembodiments, each of the first effective light-emitting regions, each ofthe second effective light-emitting regions, and each of the thirdeffective light-emitting regions are separated. In some embodiments, thefirst effective light-emitting regions, the second effectivelight-emitting regions, and the third effective light-emitting regionsare defined by multiple separate openings formed in the pixel defininglayer. In some embodiments, each first effective light-emitting regionis defined by a light-emitting layer that is driven to emit light, wherethe light-emitting layer is between opposite anodes and cathodes in adirection perpendicular to the base substrate in its corresponding firstsub-pixel. In some embodiments, each second effective light-emittingregion is defined by a light-emitting layer that is driven to emitlight, where the light-emitting layer is between opposite anodes andcathodes in a direction perpendicular to the base substrate in itscorresponding second sub-pixel. In some embodiments, each thirdeffective light-emitting region is defined by a light-emitting layerthat is driven to emit light, where the light-emitting layer is betweenopposite anodes and cathodes in a direction perpendicular to the basesubstrate in its corresponding third sub-pixel. In some embodiments,each of the first effective light-emitting regions, the second effectivelight-emitting regions, and the third effective light-emitting regionsis defined by a corresponding light-emitting layer and a correspondingelectrode (anode or cathode) transporting carriers (holes or electrons)of the light-emitting layer or part of the electrode. In someembodiments, each of the first effective light-emitting regions, thesecond effective light-emitting regions, and the third effectivelight-emitting regions is defined by at least part of the cathode and atleast part of the anode, orthographic projections of which areoverlapped on the base substrate, orthographic projections of at leastpart of the cathode and at least part of the anode do not overlap anorthographic projection of a first insulating layer on the basesubstrate, and the first insulating layer is located between the cathodeand the anode in a direction perpendicular to the base substrate. Forexample, the first insulating layer includes a pixel defining layer. Insome embodiments, each of the first sub-pixels, of the secondsub-pixels, and of the third sub-pixels includes a first electrode, alight-emitting layer located on a side of the first electrode away fromthe base substrate, and a second electrode on a side of thelight-emitting layer far from the first electrode; in the directionperpendicular to the base substrate, a second insulating layer isprovided between the first electrode and the light-emitting layer,and/or between the second electrode and the light-emitting layer, aprojection of the second insulating layer onto the base substrateoverlaps with a projection of the first electrode or the secondelectrode onto the base substrate, and the second insulating layer hasan opening; on the side facing the light-emitting layer, the opening ofthe second insulating layer may expose at least part of the firstelectrode or the second electrode, so that it may be in contact with thelight-emitting layer or an auxiliary light-emitting functional layer;each of the first effective light-emitting regions, the second effectivelight-emitting regions and the third effective light-emitting regions isdefined by a part of the first electrode or the second electrode, wherethe part is in contact with the light-emitting layer or the auxiliarylight-emitting functional layer. In some embodiments, the secondinsulating layer includes a pixel defining layer. In some embodiments,the auxiliary light-emitting functional layer may be any one or more of:a hole injection layer, a hole transport layer, an electron transportlayer, a hole blocking layer, an electron blocking layer, an electroninjection layer, an auxiliary light-emitting layer, an interfaceimprovement layer, or an anti-reflection layer. In some embodiments, thefirst electrode may be an anode and the second electrode may be acathode. In some embodiments, the first electrode may include at leasttwo stacked layers of indium tin oxide (ITO) and silver (Ag), forexample, including three stacked layers of ITO, Ag and ITO. In someembodiments, the second electrode may include any one or more of:magnesium (Mg), Ag, ITO, or indium zinc oxide (IZO), for example,including a mixed layer or alloy layer of Mg and Ag.

Each sub-pixel includes a light-emitting layer, each first sub-pixelincludes a first-color light-emitting layer located in the opening andon the pixel defining layer, and each second sub-pixel includes asecond-color light-emitting layer located in the opening and on thepixel defining layer, and each third sub-pixel includes a third-colorlight-emitting layer located in the opening and on the pixel defininglayer.

Reference is made to FIG. 8 . In FIG. 8 , the first effectivelight-emitting region of the first sub-pixel is the region pointed bythe arrow corresponding to R, the second effective light-emitting regionof the second sub-pixel is the region pointed by the arrow correspondingto G, and the third effective light-emitting region of the thirdsub-pixel is the region pointed by the arrow corresponding to B, and theframe around the effective light-emitting region is the region of thecorresponding light-emitting layer.

In some exemplary embodiments, the manufacture process of the displaysubstrate of the embodiments may include the following steps (1) to (9).In the exemplary embodiments, reference is made to FIG. 19 , and aflexible display substrate with a top-emitting structure is taken as anexample for description.

(1) A base substrate is manufactured on a glass plate.

In some exemplary embodiments, the base substrate 10 may be a flexiblebase substrate, for example, including a first flexible material layer,a first inorganic material layer, a semiconductor layer, a secondflexible material layer and a second inorganic material layer that arestacked on the glass plate. The materials of the first flexible materiallayer and the second flexible material layer are materials such aspolyimide (PI), polyethylene terephthalate (PET), or surface-treatedpolymer soft film, etc. The first inorganic material layer and thesecond inorganic material layer are made of silicon nitride (SiNx) orsilicon oxide (SiOx), etc., to improve water and oxygen resistance ofthe base substrate. The first inorganic material layer and the secondinorganic material layer may also be called a barrier layer. Thematerial of the semiconductor layer is amorphous silicon (a-si). In someexemplary embodiments, taking the laminated structure ofPI1/Barrier1/a-si/PI2/Barrier2 as an example, the preparation processthereof includes: coating a layer of polyimide on the glass plate andcuring it to form a film so as to form the first flexible (PI1) layer;depositing a barrier film on the first flexible layer to form a firstbarrier (Barrier1) layer covering the first flexible layer; depositingan amorphous silicon film on the first barrier layer to form theamorphous silicon (a-si) layer covering the first barrier layer; coatinga layer of polyimide on the amorphous silicon layer, and curing it toform a film so as to form the second flexible (PI2) layer; depositing abarrier film on the second flexible layer to form the second barrier(Barrier2) layer covering the second flexible layer, thereby completingthe manufacture of the base substrate 10.

(2) A drive structure layer is manufactured on the base substrate.

The driving structure layer includes multiple driving circuits, and eachdriving circuit includes multiple transistors and at least one storagecapacitor, such as a 2T1C, 3T1C, or 7T1C design.

In some exemplary embodiments, the manufacture process of the drivingstructure layer may refer to the following description. The manufactureprocess of the driving circuit of the first sub-pixel 21 is taken as anexample for description.

A first insulating film and an active film are sequentially deposited onthe base substrate 10, and the active film is patterned through apatterning process, to form a first insulating layer 11 covering theentire base substrate 10, and the active layer pattern arranged on thefirst insulating layer 11, where the active layer pattern includes atleast a first active layer.

A second insulating film and a first metal film are sequentiallydeposited, and the first metal film is patterned through a patterningprocess, to form a second insulating layer 12 covering the active layerpattern and a first gate metal layer pattern arranged on the secondinsulating layer 12, where the first gate metal layer pattern includesat least a first gate electrode and a first capacitor electrode.

A third insulating film and a second metal film are sequentiallydeposited, and the second metal film is patterned through a patterningprocess, to form a third insulating layer 13 covering the first gatemetal layer and a second gate metal layer pattern arranged on the thirdinsulating layer 13, where the second gate metal layer pattern includesat least a second capacitor electrode, and the position of the secondcapacitor electrode corresponds to the position of the first capacitorelectrode.

A fourth insulating film is deposited, and the fourth insulating film ispatterned through a patterning process, to form a pattern of a fourthinsulating layer 14 covering the second gate metal layer. The fourthinsulating layer 14 is provided with at least two first via holes. Partsof fourth insulating layer 14, the third insulating layer 13, and thesecond insulating layer 12 in the two first via holes are removed byetching, to expose the surface of the first active layer.

A third metal film is deposited, and the third metal film is patternedthrough a patterning process, to form a pattern of a source-drain metallayer on the fourth insulating layer 14. The source-drain metal layerincludes at least a first source electrode and a first drain electrodelocated in the display region. The first source electrode and the firstdrain electrode may be respectively connected to the first active layerthrough the first via holes.

In the driving circuit of the first sub-pixel 21 in the display region,the first active layer, the first gate electrode, the first sourceelectrode, and the first drain electrode may form a first transistor210, and the first capacitor electrode and the second capacitorelectrode may form a first storage capacitor 212. In the abovemanufacture process, the driving circuit of the second sub-pixel 22 andthe driving circuit of the third-color sub-pixel 23 may be formed at thesame time.

In some exemplary embodiments, each of the first insulating layer 11,the second insulating layer 12, the third insulating layer 13, and thefourth insulating layer 14 may use any one or more or composite layerof: silicon oxide (SiOx), silicon nitride (SiNx), or silicon oxynitride(SiON), which may be a single layer, a multi-layer or a composite layer.The first insulating layer 11 is called a buffer layer, which is used toimprove the water and oxygen resistance of the base substrate; thesecond insulating layer 12 and the third insulating layer 13 are calleda gate insulator (GI) layer; the fourth insulating layer 14 is called aninterlayer dielectric (ILD) layer. The first metal film, the secondmetal film and the third metal film are made of metal materials, such asany one or more of: silver (Ag), copper (Cu), aluminum (Al), titanium(Ti), or molybdenum (Mo), or alloy materials of the above metals, suchas aluminum neodymium alloy (AlNd) or molybdenum niobium alloy (MoNb),each of which may have a single-layer structure or a multilayercomposite structure, such as Ti/Al/Ti. The active film uses one or morematerials of amorphous indium gallium zinc oxide (a-IGZO), zincoxynitride (ZnON), indium zinc tin oxide (IZTO), amorphous silicon(a-Si), polysilicon (p-Si), sexithiophene or polythiophene, that is, thepresent disclosure is applicable to transistors manufactured based onoxide technology, silicon technology, and organic material technology.

(3) A planarization layer is formed on the base substrate on which theaforementioned pattern is formed.

In some exemplary embodiments, a planarization film of organic materialis coated on the base substrate 10 on which the aforementioned patternis formed, to form a planarization (Planarization, PLN) layer 15covering the entire base substrate 10, and masking, exposure,development processes are used to form multiple second via holes K2 inthe planarization layer 15 in the display region. The flat layer 15 inthe multiple second via holes K2 is removed by developing, to expose thesurface of the first drain electrode of the first transistor 210 of thedriving circuit of the first sub-pixel 21, the surface of the firstdrain electrode of the first transistor the driving circuit of thesecond sub-pixel 22, and the surface of the first drain electrode of thefirst transistor of the driving circuit of the third-color sub-pixel 23.

(4) A pattern of a first electrode is formed on the base substrate onwhich the aforementioned pattern is formed. In some examples, the firstelectrode is a reflective anode.

In some exemplary embodiments, a conductive film is deposited on thebase substrate 10 on which the aforementioned pattern is formed, and theconductive film is patterned through a patterning process to form thepattern of the first electrode. The first anode 213 of the firstsub-pixel 21 is connected to the first drain electrode of the firsttransistor 210 through the second via K2, the second anode 223 of thesecond sub-pixel 22 is connected to the first drain electrode of thefirst transistor of the second sub-pixel 22 through the second via K2,and the third anode 233 of the third-color sub-pixel 23 is connected tothe first drain electrode of the first transistor of the third-colorsub-pixel 23 through the second via hole K2.

In some examples, the first electrode may use a metal material, such asany one or more of: magnesium (Mg), silver (Ag), copper (Cu), aluminum(Al), titanium (Ti), or molybdenum (Mo), or an alloy material of theabove metals, such as aluminum neodymium alloy (AlNd) or molybdenumniobium alloy (MoNb), which may have a single-layer structure, or amultilayer composite structure, such as Ti/Al/Ti, etc., or a stackedstructure formed by metal and transparent conductive material, forexample, reflective material such as ITO/Ag/ITO, Mo/AlNd/ITO, etc.

(5) A pattern of a Pixel Definition Layer (PDL) layer is formed on thebase substrate on which the aforementioned pattern is formed.

In some exemplary embodiments, a pixel definition film is coated on thebase substrate 10 on which the aforementioned pattern is formed, and thepattern of the pixel definition layer is formed through masking,exposure, and development processes. The pixel definition layer 30 inthe display region includes multiple sub-pixel definition portions 302.Multiple pixel definition layer openings 301 are formed between adjacentsub-pixel definition portions 302, and the pixel definition layer 30 inthe multiple pixel definition layer openings 301 is removed bydeveloping, to expose at least part of the surface of the first anode213 of the first sub-pixel 21, at least part of the surface of thesecond anode 223 of the second sub-pixel 22, and at least part of thesurface of the third anode 233 of the third-color sub-pixel 23.

In some examples, the pixel definition layer 30 may use polyimide,acrylic, polyethylene terephthalate, or the like.

(6) A pattern of post spacers (PS) is formed on the base substrate onwhich the aforementioned pattern is formed.

In some exemplary embodiments, a film of organic material is coated onthe base substrate 10 on which the aforementioned pattern is formed, andthe pattern of post spacers 34 is formed through processes of masking,exposure, and development. The pattern of post spacers 34 may be used asa support layer and are configured to support the FMM during theevaporation process. In some examples, in the row arrangement directionof the sub-pixels, there is a repeating unit between two adjacent postspacers 34. For example, the post spacer 34 may be located in the firstsub-pixel 21 and third-color sub-pixel 23 that are adjacent.

(7) On the base substrate on which the aforementioned pattern is formed,an organic functional layer and a second electrode are sequentiallyformed.

In some examples, the second electrode is a transparent cathode. Thelight-emitting element may emit light from a side away from the basesubstrate 10 through the transparent cathode to achieve top emission. Insome examples, the organic functional layer of the light-emittingelement includes: a hole injection layer, a hole transport layer, alight-emitting layer, and an electron transport layer.

In some exemplary embodiments, the hole injection layer 241 and the holetransport layer 242 are sequentially formed through evaporation by usingan open mask on the base substrate 10 on which the aforementionedpattern is formed, then FMM is used to sequentially form, throughevaporation, a blue light-emitting layer 236, a green light-emittinglayer 216, and a red light-emitting layer 226, and then an open mask isused to sequentially form, through evaporation, the electron transportlayer 243, the cathode 244, and the light coupling layer 245. The holeinjection layer 241, the hole transport layer 242, the electrontransport layer 243, and the cathode 244 are common layers for multiplesub-pixels. In some examples, the organic functional layer may furtherinclude a microcavity adjustment layer located between the holetransport layer and the light-emitting layer. For example, after formingthe hole transport layer, FMM may be used to sequentially form, throughevaporation, a blue microcavity adjustment layer, a blue light-emittinglayer, a green microcavity adjustment layer, a green light-emittinglayer, a red microcavity adjustment layer, and a red light-emittinglayer.

In some exemplary embodiments, the organic functional layer is formed inthe sub-pixel region to realize the connection between the organicfunctional layer and the anode. The cathode is formed on the pixeldefinition layer and connected with the organic functional layer.

In some exemplary embodiments, the cathode may use any one or more ofmagnesium (Mg), silver (Ag), aluminum (Al), or use an alloy made of anyone or more of the foregoing metals, or use a transparent conductivematerial, such as indium tin oxide (ITO), or a multilayer compositestructure of metal and transparent conductive material.

In some exemplary embodiments, the light coupling layer may be formed ona side of the cathode 244 away from the base substrate 10, and the lightcoupling layer may be a common layer for multiple sub-pixels. The lightcoupling layer may cooperate with the transparent cathode to increasethe light output. For example, the material of the light coupling layermay be a semiconductor material. However, the embodiments are notlimited thereto.

(8) An encapsulation layer is formed on the base substrate on which theaforementioned pattern is formed.

In some exemplary embodiments, the encapsulation layer is formed on thebase substrate 10 on which the aforementioned pattern is formed, and theencapsulation layer may include a first encapsulation layer 41, a secondencapsulation layer 42, and a third encapsulation layer 43 that arestacked. The first encapsulation layer 41 uses inorganic material andcovers the cathode 244 in the display region. The second encapsulationlayer 42 uses organic material. The third encapsulation layer 43 usesinorganic material and covers the first encapsulation layer 41 and thesecond encapsulation layer 42. However, the embodiments are not limitedthereto. In some examples, the encapsulation layer may adopt afive-layer structure of inorganic/organic/inorganic/organic/inorganic.

The above descriptions illustrate some implementations of the presentdisclosure. It should be noted that for those skilled in the art,without departing from the principles of the present disclosure, variousimprovements and polishments may be made. These improvements andpolishments shall fall within the protection scope of the presentdisclosure.

What is claimed is:
 1. A display substrate, comprising: firstsub-pixels, second sub-pixels and third sub-pixels; wherein in a firstdirection, the first sub-pixels and the third sub-pixels are alternatelyarranged to form first sub-pixel rows, and the second sub-pixels formsecond sub-pixel rows; wherein in a second direction, the firstsub-pixel rows and the second sub-pixel rows are alternately arranged,and the first direction and the second direction are substantiallyperpendicular; wherein two first sub-pixels and two third sub-pixels intwo adjacent rows and two adjacent columns form a 2*2 array; in the 2*2array, the two first sub-pixels are in different rows and in differentcolumns, the two third sub-pixels are in different rows and in differentcolumns, connection lines of centers of the two first sub-pixels and thetwo third sub-pixels form a virtual quadrilateral, and the secondsub-pixel is within the virtual quadrilateral; wherein, for a pluralityof distances from the centers of the two first sub-pixels and thecenters of the two third sub-pixels corresponding to a same virtualquadrilateral to a center of the second sub-pixel, at least twodistances among the plurality of distances are different; wherein: thethird sub-pixel has a symmetry axis along a first oblique line directionand a symmetry axis along a second oblique line direction, and a widthof the third sub-pixel in the first oblique line direction is differentfrom that in the second oblique line direction; and/or, the firstsub-pixel has a symmetry axis along a first oblique line direction and asymmetry axis along a second oblique line direction, and a width of thefirst sub-pixel in the first oblique line direction is different fromthat in the second oblique line direction; wherein the second obliqueline direction is substantially perpendicular to the first oblique linedirection, and the second oblique line direction and the first obliqueline direction intersect both the first direction and the seconddirection; wherein some of the virtual quadrilaterals each are a firstparallelogram, and some of the virtual quadrilaterals each are a secondparallelogram; in a row direction and in a column direction, the firstparallelograms and the second parallelograms are arranged alternately;at least one interior angle of the first parallelogram and at least oneinterior angle of the second parallelogram are different.
 2. The displaysubstrate according to claim 1, wherein the two first sub-pixels and thetwo third sub-pixels corresponding to a same virtual quadrilateralsurround a second sub-pixel; a minimum distance among distances fromother first sub-pixels and other third sub-pixels outside the samevirtual quadrilateral to the surrounded second sub-pixel, is greaterthan, a minimum distance among distances from the two first sub-pixelsand the two third sub-pixels corresponding to the same virtualquadrilateral to the surrounded second sub-pixel.
 3. The displaysubstrate according to claim 1, wherein, for the plurality of distancesfrom the centers of the two first sub-pixels and the centers of the twothird sub-pixels corresponding to a same virtual quadrilateral to thecenter of the second sub-pixel, a ratio of any two distances among theplurality of distances is in a range of 0.7 to 1.3.
 4. The displaysubstrate of claim 1, wherein a difference between the distances fromthe centers of the two first sub-pixels to the center of the secondsub-pixel corresponding to a same virtual quadrilateral, is smallerthan, a difference between the distances from the centers of the twothird sub-pixels to the center of the second sub-pixel corresponding tothe same virtual quadrilateral.
 5. The display substrate of claim 4,wherein for the same virtual quadrilateral, the distances from thecenters of the two first sub-pixels to the center of the secondsub-pixel are substantially equal.
 6. The display substrate according toclaim 1, wherein: the first sub-pixel and the third sub-pixel each arean axisymmetric pattern, and a symmetry axis of at least one firstsub-pixel and a symmetry axis of at least one third sub-pixel areparallel and do not coincide; and/or, the first sub-pixel has a symmetryaxis in a first oblique direction, and the symmetry axes in the firstoblique direction of two adjacent first sub-pixels in the first obliquedirection do not coincide; and/or, the third sub-pixel has a symmetryaxis in the first oblique direction, and the symmetry axes in the firstoblique direction of two adjacent third sub-pixels in the first obliquedirection do not coincide.
 7. The display substrate of claim 1, whereinfor the second sub-pixel, a width in the first oblique line directionand a width in the second oblique line direction are different.
 8. Thedisplay substrate of claim 7, wherein for the virtual quadrilateral, thesecond sub-pixel is approximately symmetrical with respect to aconnection line of the centers of the two third sub-pixels that areadjacent in the first oblique line direction or the second oblique linedirection, and is approximately symmetrical with respect to a connectionline of the centers of the two first sub-pixels that are adjacent in thesecond oblique line direction or the first oblique line direction. 9.The display substrate according to claim 1, wherein four virtualquadrilaterals in an array form a virtual polygon, and the firstsub-pixels and the third sub-pixels are on corners or edges of thevirtual polygon, and are alternately distributed on the edges or thecorners of the virtual polygon in a clockwise direction.
 10. The displaysubstrate of claim 1, wherein the total opening area of the firstsub-pixels is x, the total opening area of the second sub-pixels is a*x,and the total opening area of the third sub-pixels is b*x, where0.5≤a≤0.8 and 1≤b≤2.2.
 11. The display substrate of claim 1, wherein thefirst sub-pixel is a red sub-pixel, the second sub-pixel is a greensub-pixel, and the third sub-pixel is a blue sub-pixel.
 12. Ahigh-precision metal mask for manufacturing the display substrateaccording to claim 1, wherein the first sub-pixel comprises a pluralityof films, the second sub-pixel comprises a plurality of films, the thirdsub-pixel comprises a plurality of films, the high-precision metal maskcomprises a plurality of opening regions, and the plurality of openingregions comprises: a first opening region corresponding to a shape and adistribution of at least one film in the first sub-pixel, or a secondopening region corresponding to a shape and a distribution of at leastone film in the second sub-pixel, or a third opening regioncorresponding to a shape and a distribution of at least one film in thethird sub-pixel.
 13. A display device, comprising a display substrate,wherein the display substrate comprises: first sub-pixels, secondsub-pixels and third sub-pixels; wherein in a first direction, the firstsub-pixels and the third sub-pixels are alternately arranged to formfirst sub-pixel rows, and the second sub-pixels form second sub-pixelrows; wherein in a second direction, the first sub-pixel rows and thesecond sub-pixel rows are alternately arranged, and the first directionand the second direction are substantially perpendicular; wherein twofirst sub-pixels and two third sub-pixels in two adjacent rows and twoadjacent columns form a 2*2 array; in the 2*2 array, the two firstsub-pixels are in different rows and in different columns, the two thirdsub-pixels are in different rows and in different columns, connectionlines of centers of the two first sub-pixels and the two thirdsub-pixels form a virtual quadrilateral, and the second sub-pixel iswithin the virtual quadrilateral; wherein, for a plurality of distancesfrom the centers of the two first sub-pixels and the centers of the twothird sub-pixels corresponding to a same virtual quadrilateral to acenter of the second sub-pixel, at least two distances among theplurality of distances are different; wherein: the third sub-pixel has asymmetry axis along a first oblique line direction and a symmetry axisalong a second oblique line direction, and a width of the thirdsub-pixel in the first oblique line direction is different from that inthe second oblique line direction; and/or, the first sub-pixel has asymmetry axis along a first oblique line direction and a symmetry axisalong a second oblique line direction, and a width of the firstsub-pixel in the first oblique line direction is different from that inthe second oblique line direction; wherein the second oblique linedirection is substantially perpendicular to the first oblique linedirection, and the second oblique line direction and the first obliqueline direction intersect both the first direction and the seconddirection; wherein some of the virtual quadrilaterals each are a firstparallelogram, and some of the virtual quadrilaterals each are a secondparallelogram; in a row direction and in a column direction, the firstparallelograms and the second parallelograms are arranged alternately;at least one interior angle of the first parallelogram and at least oneinterior angle of the second parallelogram are different.
 14. Thedisplay device of claim 13, further comprising a pixel defining layer,wherein the pixel defining layer comprises a plurality of pixel defininglayer openings, each of the first sub-pixels, the second sub-pixels andthe third sub-pixels corresponds to a pixel defining layer opening ofthe plurality of pixel defining layer openings, and shapes of the firstsub-pixel, the second sub-pixel and the third sub-pixel areapproximately the same as shapes of their respective pixel defininglayer openings.
 15. The display device according to claim 14, wherein:the first sub-pixel comprises a plurality of films, and the plurality offilms of the first sub-pixel at least partially covers a region outsidethe pixel defining layer opening; and/or, the second sub-pixel comprisesa plurality of films, and the plurality of films of the second sub-pixelat least partially covers a region outside the pixel defining layeropening; and/or, the third sub-pixel comprises a plurality of films, andthe plurality of films of the third sub-pixel at least partially coversa region outside the pixel defining layer opening.
 16. The displaydevice according to claim 14, wherein at least some of the pixeldefining layer openings corresponding to the first sub-pixels or thethird sub-pixels have different minimum distances from their respectiveadjacent openings.